Hello there, hanekeh.

I know how challenging it can be when the QuickBooks Online app isn't working as expected. Let's troubleshoot this together to ensure your VAT is calculated correctly using the app.

Unusual behavior can occur due to outdated cached data. We can resolve this by clearing out those old files.

For Android:

1. Go to Menu ☰, then tap More Options ⋮.
2. Pick Settings, then Refresh Data.
3. Tap YES to confirm.

For iOS:

1. Tap Settings, then locate General.
2. Select iPhone Storage, then QuickBooks Online app.
3. Press Offload App.

Meanwhile, we can use a web browser to ensure your VAT information is accurately captured and displayed as intended.

Please feel free to ask any additional questions in the comments, and we're here to assist.